Preparation And Properties Of Conductive Polypyrrole/metal Composite Seaweed Nonwoven Fabri

Sodium alginate is a kind of polysaccharide substance extracted from Marine plants.Sodium alginate can be dissolved in water to form a viscous solution,which is mixed with polyvalent metal ions(such as Ca²⁺)and gelatinized,which can be further made into alginate fibers or nonwoven materials.Recently,researchers have mainly used cellulose（such as cotton）and synthetic fiber（such as polyester,nylon,polypropylene）fabrics to prepare various conductive textile substrates.Conductive polymers and their composite with metal have excellent conductive ability,good stability and easy to form effective composite with textiles,which have been widely used in the development of conductive textile materials.At present,there are few researches on the development of conductive textiles based on alginate nonwovens.From the perspective of structure,the alginate molecular chain contains a large number of hydroxyl and carboxyl groups,which can easily adsorb metal ions and conductive polymer monomers on its surface and in situ synthesize conductive polymer/metal complex to enhance the conductivity,so as to obtain excellent conductive alginate fabric based conductive textile substrate.In addition,alginate nonwoven material has a certain thickness,and is loose and porous.When impacted by external force,it can make a rapid and sensitive response to pressure through the change of resistance,which is expected to become the basic material for preparing functional conductive textiles.In this paper,polypyrrole/silver（copper）composites conductive material are prepared on alginate nonwoven fabric by in-situ oxidative polymerization using pyrrole（Py）monomers as conductive polymer precursor,Ag NO₃ or Cu Cl₂ as oxidant and sodium dodecyl sulfate（SDS）as dopant.Firstly,the effects of reactant ratio,dopant concentration and reaction time on the preparation of polypyrrole/silver（copper）compositesare systematically investigated.Secondly,the structure and morphology of polypyrrole/silver（copper）compositesare analyzed by SEM,EDX,FT-IR,XRD,XPS and Raman,and the effects of polypyrrole/silver（copper）coating on the conductivity,wettability,moisture absorption,antistatic and UV resistance of alginate nonwoven fabric are explored.The results show that polypyrrole/silver（copper）can significantly improve the electrical conductivity,antistatic and UV resistance of alginate nonwoven fabric,but significantly reduce the wetting and moisture absorption.Finally,the sensitivity,response time,relaxation time,durability and sensing test to explore the polypyrrole/silver（copper）composite alginate nonwoven fabric on the pressure sensing performance,found that with the improvement of polypyrrole/silver（copper）load,the sensitivity of fabric pressure response is reduced,but the response stability has significantly improved.When polypyrrole/silver（copper）composite alginate nonwoven material is used as the pressure sensor,it can be sensitive and stable to monitor the large joint and various micro-movements of human body.Finally,the adhesion properties of polypyrrole/silver（copper）on various fabrics are compared by weight gain rate,electrical resistance,electrical conductivity,stability and sensitivity tests.The results show that alginate nonwoven fabric is an excellent conductive textile base material.This research will lay a foundation for the development of new fabric pressure sensor.